Integrating information communication technologies into medical services or the like has drawn an increasing interest across the world. The technologies essentially include a process of measuring and transmitting bio-signals and medical information and a process of analyzing and feeding back the bio-signals and the medical information. Researches on the technologies are actively ongoing across the world. A study group called a medial wireless body area network (BAN) was created by the institute of electrical and electronics engineers (IEEE) 802.15 wireless personal area network (WPAN) standardization committee, and a task group (TG) 6 was created last year under the umbrella of the IEEE 802.15 to carry out the standardization of the BAN.
A frequency band of 402 to 405 MHz is used for a medical usage across the world. Further, an industrial, scientific and medical (ISM) band and an ultra wide-band (UWB) band also can be used in transmission of bio-signals, and thus researches thereon are actively ongoing.
A body area network (BAN) is a communication network which operates primarily near the human body. More specifically, the BAN represents a communication network and communication between devices located on, in, and off the body. The BAN can be primarily applied to a medical field, and can be further applied in various fields such as games, etc. A technology developed in association with the BAN can be applied to not only the human body but also animals or living organisms whose radio environment is similarly to that of human beings, and thus can be applied to much broader fields.
The human body is a radio communication environment which is somewhat different from a personal area network (PAN). The PAN is used to solve a communication problem that occurs between an on-body device and another device separated by 10 meters or more. Therefore, transmission through the body is not a primary target transmission environment, and a factor that obstructs the radio transmission environment caused by the human body is not much problematic.
In comparison thereto, the BAN is different in a sense that the body itself is considered as a primary radio transmission environment. Communication of the BAN may have several modes. That is, there are several types of communication modes, such as, a communication mode between in-body devices, a communication mode between an in-body device and an on-body device, a communication mode between on-body devices, a communication mode between an on-body device and an off-body device, etc.
When considering such a special radio environment and various communication modes, Bluetooth or ZigBee techniques which are conventionally developed for the PAN may be unsatisfactory, and thus there is a need to develop a signal transmission technique.
A BAN technology discussed at present can be classified into a medical BAN technology and a non-medical BAN technology in terms of an application field. In terms of a channel, the BAN technology can be classified into communication from a body surface node to a coordinator, communication between body surface nodes, communication between an in-body node and a body surface node, and a communication between in-body nodes. In addition, in terms of a medium in use, the BAN technology can be classified into a wireless scheme, a wired scheme, and a scheme of using the body itself as a medium. The BAN technology can also be classified according to whether data alone is exchanged by using a built-in power source, or power is externally supplied, or power is generated internally. In case of a BAN used for medical usage, it can be roughly classified into a wearable BAN as a network between nodes attached to the body and an implant BAN as a network between implant nodes which can be implanted in the body.
The BAN is located inside/outside of the body or on the body surface and supports low costs, low complexity, ultra-low power, and highly reliable wireless communication. In addition, the BAN supports a medical application, a non-medial application, or the like.
Herein, a medical/healthcare application uses a low data rate of below 10 Kbps and ultra-low power.
In addition, the non-medical application uses a high data rate of above 10 Mbps and low power.
As such, each application has a different requirement in terms of power and a data rate. For this, there is a need for a frame structure capable of independently serving each application.